Data sheet Pack Doppler effect

Description

The Doppler effect, well known to the passage of a vehicle past a fixed observer is, thanks to the Doppler Effect Pack, experimentally quantifiable. The experiment involves measuring the frequency of a signal in motion. The pack consists of a specific mechanical motorized bench and a Initio® housing. The mechanical bench generates a constant speed movement. The mobile speed is controlled by a housing that, fitted with a drive, allows either to set different speeds or to manually generate a speed variation. This bench is designed to accommodate the Moduson® transmitter and receiver not supplied. The transmitter is placed on the movable part of the bench: its movement is controlled and it has a constant speed. The receiver, placed on the fixed part, allows to measure the perceived frequency. An initio® housing entitled "Doppler by Ultrasound", allows to deduce a frequency signal equal to the difference between the transmitted frequency and the received frequency: it is the Doppler shift. We deduce the speed of the mobile. The moving part is designed to be used with an optical fork. This allows the comparison of two velocimetry devices. In analogy with the automotive radars, the transmitter and receiver can be positioned on the same side and the moving mobile is then equipped with a screen to reflect the ultrasonic wave. Similarly, we deduce the frequency shift and conclude concerning the speed of the mobile.